Labour productivity is more procyclical in OECD countries with lower employment volatility. To capture this new stylised fact, this column proposes a business cycle model with employment adjustment costs, variable hours, and labour effort. In the model with variable effort, it shows that greater labour market frictions are associated with procyclical labour productivity as well as stable employment. In contrast, the constant-effort model fails to replicate the observed cross-country pattern in the data. Labour market deregulation has a greater effect on labour productivity cyclicality and employment volatility when effort can vary.